1. A suspension of small globules of one liquid in a second liquid with which the first will not mix: an emulsion of oil in vinegar.
2. A photosensitive coating, usually of silver halide grains in a thin gelatin layer, on photographic film, paper, or glass.
[New Latin ēmulsiō, ēmulsiōn-, from Latin ēmulsus, past participle of ēmulgēre, to milk out : ē-, ex-, ex- + mulgēre, to milk; see melg- in the Appendix of Indo-European roots.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.